Compressing centrifuge

ABSTRACT

Method and apparatus for compressing dry or wet gases wherein the gas is compressed in a high speed rotor and discharged from said rotor in essentially compressed state to a secondary rotor where the kinetic energy of the fluid stream is converted to work; this work can be then used to decrease the work input to the primary rotor, resulting in an improved efficiency for the machine. Dry gases, such as air, may be compressed; also, wet gases or vapors, with a predetermined amount of liquid, such as gas-liquid mixture of propane, may be compressed and liquefied within the said primary rotor with the fluid being a liquid when reaching the secondary rotor and being discharged as a liquid from the machine. Further, liquid may be added to a dry gas in a predetermined amount, for example, water added to air, to absorb some heat during compression and thereby decrease primary rotor speed.

United States Patent 1191 Eskeli 1451 Sept. 25, 1973 COMPRESSINGCENTRIFUGE Assistant ExaminerAllen. M. Ostrager [76] Inventor: MichaelEskeli, 6220 Orchid Ln, Attorney-Wm. T. Wofford, Robert A. Felsman,James Dallas Tex. 75230 C. Falls and Arthur F. Zobal [22] Filed: May 4,1971 [57] ABSTRACT 21] App| 140 124 Method and apparatus for compressingdry or wet gases wherein the gas is compressed in a high speed rotor anddischarged from said rotor in essentially com- [52] US. Cl 415/1,415/80, 415/83, pressed State to a secondary rotor Where the kinetic em415/147 ergy of the fluid stream is converted to work; this work [51]Int. Cl. FOld 1/06, FOld 1/22 can be then used to decrease the workinput to the [58] Fleld 0f Search 415/147, 80, 83 mary rotor, resultingin an improved efficiency for the machine. Dry gases, such as air, maybe compressed; [56] References C'ted also, wet gases or vapors, with apredetermined amount UNITED STATES ATEN S of liquid, such as gas-liquidmixture of propane, may be 1.034,1s4 7/1912 Alberger 415/147 mp ss d andliquefied within the said primary rotor 2,321,276 6/1943 Bolt 415/147with the fluid being a liquid when reaching the second- 2.33 ,62511/1943 Heppner 415/147' -ary rotor and being discharged as a liquidfrom the ma- FOREIGN PATENTS OR APPLICATIONS g F g liquid be addeld toatdry 53 pre e ermine amoun or examp e, wa er a e 0 7,637 4 1908 G B t6O 27 1,033,790 4/1953 415/1 47 am to absorb m heat durmg compress'onand thereby decrease primary rotor speed. Primary Examiner-Martin P.Schwadron 13 Claims, 4 Drawing Figures L W t Q 1e 4 r Pmmmmsm BJGIJQINVENTOR.

BY mdmze PATENTED SEPZS i975 SHEET 2 BF 3 INVENT OR.

l COMPRESSING CENTRIFUGE BACKGROUND OF THE INVENTION The inventionrelates generally to devices for compressing gases; either as a dry gasor as a wet gas with an amount of liquid fed to the compressor with thegas.

The art of compressing gases has seen variety of devices. One largegroup of such devices uses centrifugal force to accelerate the gas in animpeller, then throwing the gas to the diffuser where said gas iscompressed by converting the kinetic energy imparted to the gas by theimpeller, to pressure.

The main disadvantage of these conventional compressors is their poorefficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of one formof the compressor.

FIG. 2 is an end view of the same compressor shown in FIG. 1, as well asan embodiment of invention.

FIG. 3 is an end view of another form of the compressor and FIG. 4 is asectional view of the same compressor, as well as an embodiment of thisinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS It is an object of this inventionto provide a method and an apparatus to compress gases, either dry, orgases containing liquids, in which the gas is compressed within a rotorto approximately to its final pressure, after which the gas is passedfrom the rotor via suitable openings to a section where the kineticenergy contained by the the gas is converted to work with only minorchanges in the pressure of the gas. After the kinetic energy is absorbedby the secondary rotor, the gas is passed to the machine gas outlet incompressed condition and at a pressure that is higher than the inletpressure of said gas.

It is also an object of this invention to provide means for compressinggases with suitable properties, wherein the gas is liquefied within theprimary rotor, after which the liquid is passed from the primary rotorto the secondary rotor wherein the kinetic energy of the liquid isconverted to power; after'theliquid has been slowed to a suitablevelocity, it is passed to the outlet from said compressor in liquidform.

Referring to FIG. ll, therein is illustrated a sectional view of oneform of said compressor. 10 is a stationary compressor casing, 11 is theprimary rotor, equipped with openings 16 on the periphery and with vanes24 defining cavities within the rotor for assuring that the fluid withinsaid rotor will rotate at same velocity as the rotor. Gas is admitted tosaid primary rotor via hollow shaft opening 13; said gas may be dry ormay have a predetermined amount of liquid with it. After compression ofthe fluid by centrifugal action within the primary rotor, said fluidleaves the rotor through openings 16, and is passed to openings 17 inthe secondary rotor. The rotational velocity of the secondary rotor ismaintained to convert the kinetic energy contained in the fluid, towork, in said secondary rotor. In passage 17, vanes are placed to todeflect the said fluid stream; the design of these vanes and sizing ofthe passages is conventional and is not further described herein. 14 isthe In FIG. 2, an end view of the same compressor is shown. is thestationary housing, 11 is the primary rotor, 14 is the secondary rotor,24 are vanes in the primary rotor, 16 are openings at the periphery ofthe primary rotor, 17 are deflection vanes, or buckets, in the secondaryrotor, 18 is the annular space for collecting the fluid, 19 is the fluidoutlet, is the work output secondary rotor, 15 is the work output shaft,18 is an 6 shaft, 23 is the bearing housing, 22-is stationary housingsupport, and 25 is an indicator arrow to show the direction of rotationof said primary and secondary rotors.

In FIG. 3 an end view of a second form of the compressor is shown; themain differece being the method of converting the kinetic energycontained by the fluid, to work. 33 is the secondary rotor housing, 30is the primary rotor, 38 are primary rotor vanes, 43 indicates thedirection of rotation for the primary and secondary rotors, 36 is afluid passage in the secondary rotor, 37 is a fluid passage in theprimary rotor, 32 is a hollow shaft for fluid input and for work inputinto said primary rotor, and 39 is a support for the compressor.

In FIG. 4, a sectional view of the compressor shown in FIG. 3, isillustrated. 33 is the secondary rotor housing. The fluid to becompressed enters the compressor via hollow shaft 32 and passes toprimary rotor 30; vanes 38 within said rotor are used to accelerate thefluid to the velocity of said rotor. The fluid leaves the said primaryrotor via openings 37, and passes to secondary rotor passages 36, wherethe kinetic and rotational energy of said fluid is converted to work;the said fluid then is passed out from the compressor via hollow shaft35. 40 is a bearing, 42 is a shaft seal, and 39 and 41 are shaft bearingsupports.

The function of the compressor illustrated in FIG 1 and FlG.2, is asfollows: Gas or gas-liquid mixture, is passed to the primary rotor 11,FIG.1, where the gas is compressed by centrifugal action within therotor. Work is supplied to said rotor via shaft 13, causing said rotorand shaft to rotate at high speed. The rotational speed is determined bythe density of the gas and by the amount of compression desired. Thefluid leaves the rotor via openings 16 at the periphery of said rotor;these openings are designed and sized to retain the fluid within thesaid primary rotor until the desired amount of compression is reached.After leaving the primary rotor, the fluid will have essentially thesame velocity as the primary rotor periphery has; this high velocityfluid is then deflected in the vanes 17 of the secondary rotor. Thespeed of the secondary rotor is chosen to convert most of the kineticenergy contained in the fluid stream to work, without any major changesin the pressure of the fluid. In the illustrations, one row of vanes orbuckets are shown; more than one row may be used, with stationary bucketrows between the moving rows, if desired. The shaft 13 of the primaryrotor is connected to a power source, such as an electric motor, and theshaft of the secondary rotor is connected to a load, or may be connectedto the primary rotor shaft via a suitable powertransfer device, such asa gearbox.

The function of the compressor shown in FIG. 3 and FIG. 4 is similar tothat described above; the main difference being in the method ofconverting the velocity of the fluid leaving the primary rotor, to work.After leaving the primary rotor, the fluid enters into passages 36 inthe secondary rotor, where fluid stream is deflected in a curvingpassage, and passed to the center and out through a hollow shaft. Theconversion of kinetic energy to power in the said passage 36 ofsecondary rotor 33, functionally is similar to passages in inward-flow,turbines, or commonly known as Francis turbines. In this typearrangement, there is some pressure loss for the fluid in said passage36 due to centrifugal forces; however, this pressure loss is notsignificant due to lower angular speed of the secondary rotor; also, bysuitable design of these passages said pressure losses can be minimized.

In the compressing centrifuge described hereinbefore pressures arelowest near the center of the primary rotor and build up so that thepressure is higher near the discharge passageways. Ordinarily, thepressure near the periphery of the primary rotor is higher than thepressure in the casing, or discharge of the compressing centrifuge, toaccommodate a pressure drop of the fluid passing through the nozzles, ordischarge passageways, of the primary rotor. The fluids passing throughthe discharge passageways may attain high velocities. There may beemployed any of the conventional methods of converting to velocity thepressure drop of the compressed fluid flowing out of the dischargepassageways. For example, the primary rotor discharge passageways may besized and shaped to provide for isentropic expansion of the fluidpassing therethrough so that the higher than ordinary velocities can beattained. The proper design for such discharge passageways, or nozzles,to effect isentropic expansion is well known and is discussed instandard texts and references such as KENTS MECHANICAL ENGINEERSHANDBOOK, Power Volume, J. K. Salisbury, editor, 12th edition, WylieEngineering, Inc., New York, 1950, chapters 4-03 and -02. As discussedtherein, the discharge passageways may be slightly converging althoughthe degree of convergence is small for effecting isentropic expansion;the discharge passageways may be nonconverging; or the dischargepassageways may be diverging, as illustrated by passageways l6 and 37 inFIGS. 2 and 3.

The compressors shown can be used to compress either dry or wet gases.The compression of dry gases is essentially as described above; andinclude gases such as air, methane, and others. The compression of gasessuch as propane, ethylene or other similar gases, where the fluid mayexist in both liquid and vapor form at ambient temperatures, can beadvantageously accomplished with the compressor described in thisinvention. The vapor is passed to the compressor via the hollow shaft,with a suitable amount of liquid; the purpose of the liquid is to helpcondense the vapor, and at the same time absorb the heat of compressionand the heat of vaporization of the vapor that is being liquefied withinthe primary rotor. The fluid in this type of usage will be all liquidwhen leaving the primary rotor; normally, the primary rotor would have alayer of liquid within, although this liquid layer is not mandatory.That is, the amount of liquid may be less than the amount necessary toprovide a liquid layer. On the other hand, an amount of liquid that isgreater than the minimum amount necessary to create the liquid layer maybe employed. The fluid temperature for this liquid leaving thecompressor will be higher than the fluid entry temperature to thecompressor due to the heat of vaporization of the gas being added to it.The compressor shown in FIG.3 and F164 can advantageously be used tocompress liquid-vapor mixtures.

The two arrangements illustrated in the FIGURES differ primarily in theway the kinetic energy contained by the fluid when leaving the primaryrotor, is converted to work. Other arrangements for said conversion maybe used, some of which will be briefly listed here:

a. Mount buckets on the secondary rotor; the buckets similar to thoseused in impulse type hydraulic turbines, commonly known as Peltonwheels.

b. Convert the velocity energy to pressure in a suitable diffuser andthen lower the pressure in a suitable engine or gas expander to obtainwork; the diffuser and the gas expander may be built within the samehousing as the compressor.

Further, to decrease the speed of the primary rotor for a given amountof compression, liquid may be added to the compressor inlet. Example forthis would be the addition of water when compressing air; the waterwould absorb some of the heat of compression and thereby increase thedensity of the air within the primary rotor.

I claim:

1. A method of compressing a fluid comprising:

a. subjecting said fluid to a centrifugal force field via a primaryrotor having vanes defining cavities to ensure that said fluid attainsthe same rotational speed as said rotor, in a compressing centrifuge tocompress said fluid to a pressure that is higher than the dischargepressure from said compressing centrifuge;

b. passing said fluid in its compressed state through dischargepassageways that are smaller in cross sectional area than the area ofsaid respective cavities intermediate said vanes upstream thereof andthat are located on the periphery of said primary rotor such thatcentrifuging action is effected and essentially the same velocity asthat of the primary rotor periphery is imparted to said fluid from saidprimary rotor to a secondary rotor in which a large portion of thekinetic energy contained by said fluid is extracted and converted touseful work; and

c. passing said fluid in its compressed state from said secondary rotorto a compressing centrifuge outlet, the pressure of said fluid at saidcompressing centrifuge outlet being higher than at said compressingcentrifuge inlet.

2. A method of compressing a fluid comprising:

a. subjecting said fluid and a liquid forming a gasliquid mixture to acentrifugal force field via a primary rotor having vanes definingcavities to ensure that said gas-liquid mixture attains the samerotational speed as said rotor, in a compressing centrifuge to compresssaid gas-liquid mixture to a pressure that is higher than the dischargepressure from said compressing centrifuge; the liquid being fed to thecompressing centrifuge at the primary rotor at a predetermined rate toform said gas-liquid mixture; said gas-liquid mixture including anyadditional liquid formed by condensation and solution of the fluid inthe liquid injected there-into because of the centrifuging action andthe centrifugal force field;

b. passing said gas-liquid mixture in its compressed state throughdischarge passageways that are smaller in cross sectional area than therespective said cavities intermediate said vanes upstream thereof andthat are located on the periphery of said primary rotor such thatcentrifuging action is effected and essentially the same velocity asthat of the primary rotor periphery is imparted to said fluid from saidprimary rotor to a secondary rotor in which a large portion of thekinetic energy contained in said gas-liquid mixture is extractedtherefrom and converted to useful work; and

c. passing said gas-liquid mixture to the compressing centrifuge outlet,the outlet pressure being higher than the compressing centrifuge inletpressure.

3. The method of claim 2 wherein at least a portion ofthe fluid to becompressed is liquefied within the primary rotor and is passed therefromthrough the secondary rotor to the compressing centrifuge outlet in itsliquid state, and wherein part of the heat of compression is absorbed bythe fluid in its liquid state.

4. The method of claim 2 wherein the liquid being added to the fluid atthe compressing centrifuge inlet is different from said fluid, theliquid being added for the purpose of absorbing part of the heat ofcompression of the gas.

5. The method of claim 2 wherein the liquid being added to said fluid atthe compressing centrifuge inlet is liquid phase of said fluid.

6. The method of claim 2 wherein said fluid is subjected to isentropicexpansion in passing through discharge passageways from said primaryrotor for increased kinetic energy.

7. A compressing centrifuge for compressing fluids comprising:

a. a primary rotor means for subjecting said fluid to a centrifugalforce field; said primary rotor means having a space with internal vanesdefining respective cavities within said primary rotor for ensuring thatany fluid within said primary rotor means rotates with the same velocityas said primary rotor means; said primary rotor means being equippedwith means for introducing the fluid to be compressed at the center ofsaid primary rotor means and having suitable discharge passagewaysadjacent the periphery thereof for discharging the compressed saidfluid; said discharge passageways being smaller in cross sectionaldimensions than the minimum cross sectional dimension of the associatedcavity; said primary rotor means also having 6 a shaft for power inputneeded to effect rotation thereof; and

b. a secondary rotor means for absorbing and convetting to useful work alarge portion of the kinetic energy of said fluid in its compressedstate leaving the discharge passageways of said primary rotor means;said secondary rotor means having suitable vane means for absorbingenergy from the fluid stream as it leaves the discharge passageways ofsaid primary rotor means.

8. The compressing centrifuge of claim 1 wherein said secondary rotormeans also serves as a casing with the compressed fluid being dischargedvia the center shaft thereof, said center shaft also effecting deliveryof the power to accomplish said useful work.

9. The compressing centrifuge of claim 7 wherein a casing is providedfor said primary and secondary rotor means; said casing having suitableseals and bearings for support of the respective shaft supporting saidprimary and secondary rotor means and for containing said fluid;saidcasing having respective passageways through which said fluid may betaken in and discharged respectively.

10. The compressing centrifuge of claim 7 wherein said dischargepassageways of said primary rotor means are shaped for effectingisentropic expansion of said fluid passing therethrough.

11. The compressing centrifuge of claim 10 wherein said dischargepassageways are at least nonconverging at their discharge end section.

12. The compressing centrifuge of claim 11 wherein said dischargepassageways ar'e diverging at their discharge end section.

13. The compressing centrifuge of claim 7 wherein a diffuser passage isprovided downstream of the secondary rotor vanes for increasing thepressure of the fluid where only a part of the kinetic energy containedin the fluid stream is converted'to work via the secondary rotor means;said diffuser passage effecting some conversion of the kinetic energy toincrease the pressure of the fluid at the discharge of said compressor.

1. A method of compressing a fluid comprising: a. subjecting said fluidto a centrifugal force field via a primary rotor having vanes definingcavities to ensure that said fluid attains the same rotational speed assaid rotor, in a compressing centrifuge to compress said fluid to apressure that is higher than the discharge pressure from saidcompressing centrifuge; b. passing said fluid in its compressed statethrough discharge passageways that are smaller in cross sectional areathan the area of said respective cavities intermediate said vanesupstream thereof and that are located on the periphery of said primaryrotor such that centrifuging action is effected and essentially the samevelocity as that of the primary rotor periphery is imparted to saidfluid from said primary rotor to a secondary rotor in which a largeportion of the kinetic energy contained by said fluid is extracted andconverted to useful work; and c. passing said fluid in its compressedstate from said secondary rotor to a compressing centrifuge outlet, thepressure of said fluid at said compressing centrifuge outlet beinghigher than at said compressing centrifuge inlet.
 2. A method ofcompressing a fluid comprising: a. subjecting said fluid and a liquidforming a gas-liquid mixture to a centrifugal force field via a primaryrotor having vanes defining cavities to ensure that said gas-liquidmixture attains the same rotational speed as said rotor, in acompressing centrifuge to compress said gas-liquid mixture to a pressurethat is higher than the discharge pressure from said compressingcentrifuge; the liquid being fed to the compressing centrifuge at theprimary rotor at a predetermined rate to form said gas-liquid mixture;said gas-liquid mixture including any additional liquid formed bycondensation and solution of the fluid in the liquid injected there-intobecause of the centrifuging action and the centrifugal force field; b.passing said gas-liquid mixture in its compressed state throughdischarge passageways that are smaller in cross sectional area than therespective said cavities intermediate said vanes upstream thereof andthat are located on the periphery of said primary rotor such thatcentrifuging action is effected and essentially the same velocity asthat of the primary rotor periphery is imparted to said fluid from saidprimary rotor to a secondary rotor in which a large portion of thekinetic energy contained in said gas-liquid mixture is extractedtherefrom and converted to useful work; and c. passing said gas-liquidmixture to the compressing centrifuge outlet, the outlet pressure beinghigher than the compressing centrifuge inlet pressure.
 3. The method ofclaim 2 wherein at least a portion of the fluid to be compressed isliquefied within the primary rotor and is passed therefrom through thesecondary rotor to the compressing centrifuge outlet in its liquidstate, and wherein part of the heat of compression is absorbed by thefluid in its liquid state.
 4. The method of claim 2 wherein the liquidbeing added to the fluid at the compressing centrifuge inlet isdifferent from said fluid, the liquid being added for the pUrpose ofabsorbing part of the heat of compression of the gas.
 5. The method ofclaim 2 wherein the liquid being added to said fluid at the compressingcentrifuge inlet is liquid phase of said fluid.
 6. The method of claim 2wherein said fluid is subjected to isentropic expansion in passingthrough discharge passageways from said primary rotor for increasedkinetic energy.
 7. A compressing centrifuge for compressing fluidscomprising: a. a primary rotor means for subjecting said fluid to acentrifugal force field; said primary rotor means having a space withinternal vanes defining respective cavities within said primary rotorfor ensuring that any fluid within said primary rotor means rotates withthe same velocity as said primary rotor means; said primary rotor meansbeing equipped with means for introducing the fluid to be compressed atthe center of said primary rotor means and having suitable dischargepassageways adjacent the periphery thereof for discharging thecompressed said fluid; said discharge passageways being smaller in crosssectional dimensions than the minimum cross sectional dimension of theassociated cavity; said primary rotor means also having a shaft forpower input needed to effect rotation thereof; and b. a secondary rotormeans for absorbing and converting to useful work a large portion of thekinetic energy of said fluid in its compressed state leaving thedischarge passageways of said primary rotor means; said secondary rotormeans having suitable vane means for absorbing energy from the fluidstream as it leaves the discharge passageways of said primary rotormeans.
 8. The compressing centrifuge of claim 1 wherein said secondaryrotor means also serves as a casing with the compressed fluid beingdischarged via the center shaft thereof, said center shaft alsoeffecting delivery of the power to accomplish said useful work.
 9. Thecompressing centrifuge of claim 7 wherein a casing is provided for saidprimary and secondary rotor means; said casing having suitable seals andbearings for support of the respective shaft supporting said primary andsecondary rotor means and for containing said fluid; said casing havingrespective passageways through which said fluid may be taken in anddischarged respectively.
 10. The compressing centrifuge of claim 7wherein said discharge passageways of said primary rotor means areshaped for effecting isentropic expansion of said fluid passingtherethrough.
 11. The compressing centrifuge of claim 10 wherein saiddischarge passageways are at least nonconverging at their discharge endsection.
 12. The compressing centrifuge of claim 11 wherein saiddischarge passageways are diverging at their discharge end section. 13.The compressing centrifuge of claim 7 wherein a diffuser passage isprovided downstream of the secondary rotor vanes for increasing thepressure of the fluid where only a part of the kinetic energy containedin the fluid stream is converted to work via the secondary rotor means;said diffuser passage effecting some conversion of the kinetic energy toincrease the pressure of the fluid at the discharge of said compressor.